1. Field Of The Invention
This invention relates to defoamer emulsion compositions for use in textile dyeing operations.
2. Description Of Related Art
Defoamers used in textile dyeing must be efficient at reducing foam in aqueous media such as aqueous dyebaths. Most commercial defoamers used in textile dyeing operations are silicone-based materials containing about 15% by weight of silicone. Defoamers containing such amounts of silicone suffer from the disadvantage that some of the defoamer material adheres to the fibers being dyed resulting in non-uniform dye application. In addition, silicone-based defoamers may not be sufficiently stable in aqueous media, such as dyebaths.
Non-silicone defoamers have been developed to overcome the problems characteristic of silicone-based defoamers. Non-silicone defoamers, while exhibiting better stability and producing more uniform dyeing than commercial silicone containing defoamers also have disadvantages. They are difficult to disperse in aqueous media at low temperatures (e.g. about 1.degree. C.). They require higher concentrations than is customary for silicone-based defoamers. Also, while the non-silicone defoamers are more stable that their silicone-containing counterparts, there is still a need for more stable defoamers, particularly for bleach systems, synthetic fiber dyebaths and wool dyebaths.
The defoamers according to the invention provide advantages over both standard silicone containing defoamers and those that do not contain silicone because they are stable in bleach systems, as well as synthetic fiber and wool dyebaths. They can readily be dispersed in water at low temperatures and may be used in lower concentrations than previous defoamers.